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71.
A sexually dimorphic ratio of orbitofrontal to amygdala volume is altered in schizophrenia. 总被引:3,自引:0,他引:3
Raquel E Gur Christian Kohler Bruce I Turetsky Steven J Siegel Stephen J Kanes Warren B Bilker Avis R Brennan Ruben C Gur 《Neuropsychopharmacology》2004,55(5):512-517
BACKGROUND: Neuroanatomic sexual dimorphisms have been correlated with behavioral differences between healthy men and women. We have reported higher orbitofrontal cortex to amygdala ratio (OAR) in women than men. Although gender differences in schizophrenia are evident clinically and correlate with neuroanatomic measures, their relationship to OAR has not been examined. METHODS: Magnetic resonance imaging was performed in 31 neuroleptic-na?ve schizophrenic patients (16 men) and 80 healthy volunteers (34 men), aged less than 50 years. An automated tissue segmentation procedure was combined with expert-guided parcellation of orbitofrontal and amygdala volumes. RESULTS: Men with schizophrenia had increased OAR relative to healthy men, whereas women had decreased OAR. Increased OAR in men with schizophrenia reflected abnormally low amygdala volumes, whereas decreased OAR in women reflected abnormally low orbitofrontal volumes. Less severe negative symptoms were associated with increased OAR in men but with decreased OAR in women. In men, increased amygdala volume was associated with greater symptom severity, whereas in women higher volumes of both amygdala and orbitofrontal regions were associated with lesser severity of negative symptoms. CONCLUSIONS: These opposite OAR abnormalities, whereby men show feminization and women masculinization, suggest gender-mediated effects of the underlying neuropathologic processes. The correlations with symptom severity suggest that neuroanatomic abnormalities in OAR reflect compensatory brain changes. 相似文献
72.
Sandeep Nijhawan Mukul Rastogi Ashish Joshi Atul Shende Manish Tandon Dinesh Singla Amit Mathur Subhash Nepalia Ramesh Roop Rai 《Digestive endoscopy》2007,19(2):80-82
Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision. 相似文献
73.
George Lourenço PhD Sabine Meunier MD PhD Marie Vidailhet MD PhD Marion Simonetta‐Moreau MD PhD 《Movement disorders》2007,22(4):523-527
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles. 相似文献
74.
目的总结多发性硬化(MS)患者的临床特点(精神情感障碍)以及脑脊液、诱发电位、影像学改变进行分析。方法回顾分析65例MS患者的有关临床和实验室资料。结果65例中,男17例,女48例;年龄16~68岁,平均(36.5±14.1)岁,男女比为1∶2.8。MS首发及常见症状为感觉异常、肢体无力、视力减退及括约肌功能障碍,病变部位以脊髓受累最多见,部分患者存在精神情感障碍。结论出现感觉异常有助于MS早期诊断,诱发电位及MRI有助于发现亚临床病变;括约肌功能异常多见,可能与脊髓受累较多有关;MS患者的精神情感应受人们关注。 相似文献
75.
新生儿缺氧缺血性脑病的MRI表现 总被引:1,自引:0,他引:1
目的:探讨新生儿缺氧缺血性脑病(HIE)的MRI表现。材料和方法:对87例临床确诊为HIE的患儿行MRI扫描,并对其MRI表现进行分析。结果:87例HIE患儿中,74例(85.1%)可见皮层、皮层下及深部白质T1WI迂曲条状、点状高信号;69例(79.3%)显示基底节、丘脑T1WI异常高信号及内囊后肢高信号消失;62例(71.3%)出现弥漫性脑水肿;58例(66.7%)可见颅内出血,包括蛛网膜下腔出血、硬膜下出血、脑室内出血及脑实质出血;19例(21.8%)可见侧脑室周围白质软化;7例(8.0%)可见脑梗死。结论:MRI在HIE正确诊断和早期治疗中具有重要临床价值。 相似文献
76.
Sheetal Chopra Anna S Lev-Toaff Fatih Ors Diane Bergin 《Journal of ultrasound in medicine》2006,25(5):617-27; quiz 629
OBJECTIVE: The purpose of this presentation is to show the imaging findings of the common and uncommon variants of adenomyosis as seen on sonography and magnetic resonance imaging (MRI). METHODS: A 3-year database search was performed to identify women who had pelvic sonography and pelvic MRI within a 6-month interval. Images of these cases were retrospectively reviewed. RESULTS: Eighty women were identified. Adenomyosis was diagnosed on MRI, which was used as the reference standard, in 45 of these women. The correct diagnosis was made on sonography in 73% of the cases. CONCLUSIONS: Awareness of the spectrum of imaging features of adenomyosis is important to use sonography effectively for diagnosing this entity and to help avoid misdiagnosis. 相似文献
77.
目的 观察磁性远红外寝具对高脂血症患者血脂、血糖及抗氧化作用的影响。方法 60例高脂血症患者,按随机数字表法分为实验组(30例)和对照组(30例)。实验组每晚(6~8h)均使用磁性远红外寝具,连续2个月。对照组用普通寝具。两组均于实验前后取全血,测定血脂、血糖及抗氧化指标等。结果 实验组实验后血清总胆固醇,甘油三酯含量明显低于实验前;实验前后血清高密度脂蛋白胆固醇(HDL-ch)含量及血糖无明显变化(P〉0.05)。实验组实验后MDA含量较实验前显著下降(P〈0.05),而血清超氧化物歧化酶(SOD)活性较实验前显著提高(P〈0.01);实验前后血清中NO含量无明显变化(P〉0.05)。对照组实验前后以上各项指标较实验前均无明显变化,差异均无显著性(P〉0.05)。结论 磁性远红外寝具对高脂血症患者具有降血脂作用及抗氧化作用。 相似文献
78.
额叶外伤后早期数字工作记忆的fMRI研究 总被引:5,自引:1,他引:4
目的:利用功能磁共振成像技术研究额叶外伤后,执行工作记忆任务时脑结构损伤与脑激活功能区的改变。材料和方法:对10例额叶外伤后早期患者(伤后平均31d,其中男性7例,女性3例;平均年龄30.1年)和12例正常志愿者作为对照组(男性7例,女性5例;平均年龄26.9年)分别进行2位和4位数字的正反序工作记忆的实验,使用single-trial设计方法;GE3.0T磁共振机扫描、采集图像,运用AFNI软件包进行数据分析。结果:①正常对照组反序4位数字任务大于正序4位数字脑区有辅助运动区SMA,双侧背外侧前额叶,左侧顶叶,右侧角回;②患者组反序4位数字任务大于正序4位数字的脑区有左侧枕叶;③正常对照组反序4位数字任务大于患者组的部位有左侧DLPFC,左侧角回;正序4位数字大于患者组的部位有左侧枕叶,右侧角回;④患者组反序4位数字任务时大于对照组的部位有楔状回,右侧Broca区;正序4位数字大于对照组的部位有右侧初级运动区MA,右侧额极区。结论:前额叶在脑工作记忆网络中处于重要节点,大脑右侧半球在工作记忆系统中起到巨大代偿作用的脑资源,fMRI提供认知功能损伤的影像学依据,应在临床上发挥更大作用。 相似文献
79.
J. Kassubek A.-D. Sperfeld A. Baumgartner H.-J. Huppertz A. Riecker F. D. Juengling 《European journal of neurology》2006,13(8):880-886
Hereditary spastic paraparesis (HSP) is a heterogeneous group of neurodegenerative disorders with progressive lower limb spasticity, categorized into pure (p-HSP) and complicated forms (c-HSP). The purpose of this study was to evaluate if brain volumes in HSP were altered compared with a control population. Brain volumes were determined in patients suffering from HSP, including both p-HSP ( n = 21) and c-HSP type ( n = 12), and 30 age-matched healthy controls, using brain parenchymal fractions (BPF) calculated from 3D MRI data in an observer-independent procedure. In addition, the tissue segments of grey and white matter were analysed separately. In HSP patients, BPF were significantly reduced compared with controls both for the whole patient group ( P < 0.001) and for both subgroups, indicating considerable brain atrophy. In contrast to controls who showed a decline of brain volumes with age, this physiological phenomenon was less pronounced in HSP. Therefore, global brain parenchyma reduction, involving both grey and white matter, seems to be a feature in both subtypes of HSP. Atrophy was more pronounced in c-HSP, consistent with the more severe phenotype including extramotor involvement. Thus, global brain atrophy, detected by MRI-based brain volume quantification, is a biological marker in HSP subtypes. 相似文献
80.
W. Küker I. Mader T. Nägele M. Uhl C. Adolph U. Klose U. Herrlinger 《European journal of neurology》2006,13(8):819-826
Progressive multifocal leukoencephalopathy (PML) is caused by the replication of JC virus in oligodendrocytes of immunocompromised patients. Diagnosis usually relies on the polymerase chain reaction (PCR)-based demonstration of JC virus DNA in the cerebrospinal fluid. As previous reports have suggested that some patients may benefit from antiviral therapy, non-invasive early diagnosis is highly desirable. Repetitive magnetic resonance imaging (MRI) examinations (two to nine) were obtained in seven patients (aged 40–67 years, six males, one female) with classical clinical and imaging findings of PML. Five patients had underlying hematological disorders and two acquired immune deficiency syndrome. PCR of the cerebrospinal fluid (CSF) specimen was positive for JC virus DNA in six patients. MRI sequences included T2-, T1- and diffusion-weighted (DW) images in all patients and diffusion-tensor imaging (DTI) in four cases. DTI was once performed at 3T, in the remaining patients at 1.5T. All patients received antiviral treatment with cidofovir in addition to the treatment of the underlying disorder. MRI showed areas of T2 hyperintensity with involvement of the subcortical U-fibers and restricted diffusion in all patients. Areas of diffusion abnormality correlated with disease progress. Contrast enhancement was encountered once after successful treatment and heralded clinical remission with virus elimination from the CSF. Hence, MRI including DW and contrast-enhanced images may be used to evaluate disease activity. Contrast enhancement may indicate an inflammatory response and thus herald immunologic virus elimination. 相似文献